Foam depositor system



F. D. PETERSON FOAM DEPOSII'OR SYSTEM March 8, 1966 5 Sheets-Sheet 1Filed March 19, 1962 IO N INVENTOR. Fred D. Peterson March 8, 1966 F. D.PETERSON FOAM DEPOSITOR SYSTEM 5' Sheets-Sheet 2 Filed March 19, 1962Nvm 5N NNN whm INVENT OR. Fred D. Peterson FOAM DEPOSITOR SYSTEM FiledMarch 19, 1962 5 Sheets-Sheet 5 68 3 5 1 :i J i :;/23

INVENTOR Fred D. Peterson .l 7; BY

, A v 5 f MJf MMJ 2 March 8, 1966 F. D. PETERSON FOAM DEPOSITOR SYSTEM 5Sheets-Sheet 5 Filed March 19, 1962 INVENTOR. Fred D. Peterson UnitedStates Patent 3,239,1tlt9 FGAM DEPUSITOR SYSTEM Fred D. Peterson, SanMateo tCounty, Calif, assignor to Peterson Products of San Mateo, Ind,Belmont, Calif. Fiied Mar. 19, 1962, Ser. No. 1%,629 2 Claims. (Cl.22257) This invention relates to a new and improved chemical foamdepositor system and more particularly one having use wherein threeingredients (including a foaming agent) are pumped through a commondispensing head for deposit in a preselected location. In the form ofthe invention hereinafter described, the three ingredients comprise tworesin components and a foaming agent such as bichlorodifiuoromethane(Freon 12). The mixing of these three ingredients in accordance with thesystem hereinafter described dispenses a rigid polyether urethane(polyurethane) foam. It will be understood that the system hasapplication to other products, preferably of the type wherein twoingredients are desirably mixed only immediately prior to dispensing andhence are maintained separated until they are mixed with one or both ofthe ingredients at approximately the time that the two components arethemselves mixed together.

The present invention employs in its system three positive displacementproportioning pumps which are completely air operated, and are linkedpneumatically, as hereinafter described in detail, in such manner as toinsure that the three pumps operate synchronously. Accordingly, preciseproportioning of the components and the Freon is obtained by means ofconvenient manual external adjustment of two of the pumps. Speedcontrols for the pumps are preferably installed at a master controlconsole wherein valves are provided for independent regulation of theair pressure driving each of the three pumps, thereby compensating forvariations in the relative viscosities of the three ingredients.

The system hereinafter described provides for adjustment of the quantityof discharge of foam, the proportioning of the ingredients relative toeach other, and adjustment for viscosity of the ingredients.

The present invention comprises an air motor for one of the three pumps,namely the particular pump which must deliver the largest volume of thethree ingredients. The valve control for the air motor is modified fromconventional pump motors of this type in that the single valve is usedto control the air supply for the air motors for all three pumps. Byadjusting the air supply of the main pump, the rate of discharge of thispump may be controlled and such adjustment affects and regulates thedischarge of the entire system. The other two pumps (slave pumps) arepreferably regulated in length of stroke by manual adjustment. Thesystem is so regulated that each pump makes the same number of strokesper time interval, and hence regulating the stroke of the two slavepumps which are driven synchronously with the main pump varies theproportion of the other two ingredients relative to the ingredientsdispensed by the main pump. It will further be understood that theviscosity of the various ingredients may vary from time to time. Suchvariations may be partially cotrolled by heating the components to makethem less viscous. However, the system also provides means forcontrolling the air pressure to the two slave pump motors in order toinsure that the pump pistons of the three pumps move at approximatelythe same speed. If the three pumps are so regulated in their air supplythat the pistons thereof move at the same speed, and since the number ofstrokes of the pumps is identical, the discharge of the three pumpsbrought together in the dispensing head will be of constant proportionand for practical purposes homogeneous.

A further feature of the invention is the fact that the pumps proportionaccurately with all three of the components of the foam in phase.

A further feature and advantage of the invention is the fact that thepumps are preferably driven by compressed air from a conventional aircompressor. Thus no high voltage alternating current electric motors arerequired in the system, as contrasted with proportioning systems whereingear pumps driven by electric motors must be employed. The absence ofhigh voltage current is a feature of particular advantage in that atintervals the equipment must be flushed out with a solvent and manycommonly used solvents are explosive.

A further feature and advantage of the invention is the fact that thepumps are of positive displacement type and hence the quantity of foamdispensed for each stroke of the pump is uniform. By counting thestrokes the amount of foam dispensed can be calculated with ease.

A still further feature and advantage of the invention is the lowmaintenance cost in that any of the positive displacement pumps can berepaired by merely replacing cylinder and packings with standard parts.This is of particular importance in that pumps used in systems handlingthis type of equipment tend to wear rapidly because of crystals fromTDI, (toluene diisocyanate).

Another feature of one form of the invention is the fact that the pumpsneed not recirculate. Where electric motor driven pumps are employed, arelief valve must be provided for recirculation of the pump liquid backto its source to prevent stalling the motor. The present inventioneliminates the need of recirculating the ingredients. Where heattransfer is a problem which might otherwise indicate that recirculationshould be attempted, the thick walls of the hoses used in accordancewith the pres ent invention provide sufiicient heat insulation so thatrecirculation is not necessary.

Still another feature of the invention is the fact that the ingredientsare agitated immedaitely prior to and as they are being dispensed fromthe head in which they are mixed together. Premature mixing of theingredients is avoided and hence an effective foam is produced.

The console and the air supply, which is distributed by means ofmanifolds at the console, may be used not only to drive an air turbinefor the dispensing head and the pumps heretofore mentioned, but alsovarious types of auxiliary equipment such as air masks for operators,air spraying apparatus, and a system for cleaning the apparatus by meansof solvents.

A feature of the invention is its ready portability in that the consoleand the containers for the various ingredients may all be mounted on acart supporting a mast and articulated booms for support and enclosureof vmaterial and control flow lines which lead to a dispensing headlocated at the outer end of the booms.

The dispensing head used in accordance with this system has a number offeatures and advantages. Essentially the head consists of a mixingchamber in which the three ingredients are brought together and agitatedand from which they are discharged at a pressure at least as great asthe vapor pressure of the foaming agent. The dispensing head is soconstructed that back pressures are created throughout the chamber,thereby insuring proper mixing of the various ingredients.

A particular feature of the construction of the dispensing head is themeans incorporated therein whereby the components are admitted to themixing chamber and which insures proper mixing of the ingredients. Thusthe foaming agent and the lighter of the two components are so directedinto the mixing chamber that they first contact a rotating rod or shafthaving a roughened or knurled surface, the surface friction of whichblends the foaming agent and the first of the components together. Theheavier component is preferably separately introduced to the mixture oflighter component and foaming agent. A further feature of theconstruction of the entrance end of the mixing chamber is the fact thatan agitator is located at this Zone, which agitator comprises apropeller constructed with a reverse thrust, the propeller preferablybeing shrouded along its outer tip so that the heavier ingredient willbe directed back for recirculation through the propeller. Preferably theparticular component having the thinnest viscosity and also preferablythat not having TDI comes in contact with the propeller shaft along withthe foaming agent (Freon). This results in a thorough mixing of thethinnest component and the foaming agent and the mixture of these twoingredients is then mixed with the thicker component. The threeingredients are thoroughly stirred by means of a series ofturnstile-type stirring rods. A second propeller, which likewise has areverse thrust, is located at the bottom of the agitator chamber, againinsuring a back pressure which maintains the chamber filled at alltimes.

The mixing chamber is closed off at its lower end by means of a caphaving its discharge orifice located displaced from the center of thecap. Hence the center of the cap may constitute the bottom bearing forthe agitator shaft. A further feature of this construction is the factthat the fluid may constitute its own lubricant, lubricating themetal-to-metal contact.

The control handle which governs the delivery of components to the headis provided with a cam which controls an air valve supplying pilot airto shut off the pumps for the ingredients. The pumps serve as their ownaccumulators and when their strokes are discontinued they do notcontinue to pump against a static head. When the control handle is againturned on and the pumps resume operation, even the first materialdeposited is well mixed, as contrasted with other systems wherein thethin viscosity component tends to spurt out ahead of the othercomponents.

Other features of the dispensing head relate to safety. Thus thedispensing head is held in assembled position by means of a yoke whichhas eye bolts, the eyes of which are not welded together. In the eventof a build-up of pressure the eyes tend to open gradually and enable thecaps at either end of the dispensing barrel to move apart relative toeach other so that the components within the mixing chamber can escapewithout explosion.

A further feature of the construction is the fact that the caps aresealed to the barrel by means of O-rings seated in butt joints. Hencethe ingredients tend to blow out sideward as contrasted withconventional means of sealing caps to opposite ends of a chamber barrel.Again, this construction reduces danger of explosion.

The foregoing construction likewise makes the assembly of the partsrapid and facilitates cleaning of the mechanism at the end of its use.

Still another feature of the invention is the fact that the Freon orfoaming agent is emitted into the mixing chamber only when the pressureexceeds that of a check valve located below the mixing chamber. Apositive pressure head is maintained on the top of the Freon tank bymeans of a nitrogen cylinder. The nitrogen is also available to fill theheads of the tanks for the other components.

Another advantage of the invention is the provision of means forflushing the dispensing or mixing head with solvent. A three-way valveis actuated manually to provide pressure in the tank for solvent.

A still further feature of the invention is the provision of a backpressure mechanism consisting of a tubular back pressure diaphragmlocated below the mixing chamher. The Freon or other foaming agent mustbe maintained at a pressure above about 80 p.s.i., its vapor pressure.The diaphragm insures that no product will be dispensed. at a pressurebelow such pre-selected pressure. The back pressure mechanism is soconstructed that it will only open and discharge foam when the pressureis above a predetermined amount, which amount is regulated by the valve.This insures that the mixed ingredients will be discharged in the formof a froth foam. An on-olf operation is obtained with very little lossof product or spillage.

An advantage of the foregoing construction is that the flow is straightthrough when the mechanism is open rather than pursuing a circuitouspath as in other pressure regulators. No seats are required for valvesand leakage is for practical purposes eliminated. The device compensatesfor changes in volume and further is selfindicating as to whether theproduct is being discharged.

Below the back pressure regulator is an expansion chamber which collectsthe product discharged from. the regulator and prevents the product frombeing emitted in a swirling fashion. This insures proper filling of acavity, mold or the like with foam.

Other objects and advantages of the invention will become apparent uponreading the following specification and referring to the accompanyingdrawings in which similar characters of reference representcorresponding parts in the several views.

In the drawings:

FIG. 1 is a substantially diagrammatic front elevational view of thecomponents making up the system;

FIG. 2 is a schematic piping diagram for the system, tubular membersbeing illustrated by single lines;

FIG. 3 is a longitudinal sectional view of the master pump, its airmotor, valve construction and associated elements;

FIG. 4 is a longitudinal midsectional view through one of the adjustablestroke pumps and its air motor;

FIG. 5 is a longitudinal midsectional view through the dispensing head,back pressure regulator, and associated mechanism;

FIG. 6 is a fragmentary, enlarged sectional view of the upper end of thedispensing head;

FIG. 7 is a transverse sectional view taken substantially along line 77of FIG. 5; and

FIG. 8 is a side elevation of the structure of FIG. 5.

As best shown in FIG. 1 there is provided a carriage 21 in the form of adolly on which many of the components hereinafter described are mountedand transported. Such a dolly is readily portable from job to job.Mounted on dolly 21 is console 22 containing various valves, gauges andthe like hereinafter described in detail. For convenience, one of theadjustable stroke pumps, namely that pump 25 which emits Freon, may bemounted on console 22. Dolly 21 also carried two large drums, 23 and 24,containing component A and component B. Component A drum 23 ispreferably that particular plastic ingredient which is consumed in thelargest volume. Pump 26 for component A is of a fixed stroke and isdriven by means of air motor 27. Air motor 27 and its valve constructionare hereinafter described in greater detail. Component B drum 24 islikewise provided with pump 28 which is preferably adjustable in itsstroke and is driven by its own air motor 29, likewise as hereinafterdescribed. Dolly 21 may also be used to transport other equipment whichis shown for convenience in FIG. I removed from the dolly but which inactual practice is preferably mounted thereon. Thus a cylinder 31 ofliquified Freon gas is used. A second cylinder 32 of nitrogen gas usedto fill the Freon cylinder head space may be used. Further a pot 33 ofsolvent for flushing out the mechanism may likewise be so mounted.

It will be understood that components A and B and Freon are used toproduce a polyurethane foam for which the invention is particularlysuitable. However, other ingredients may be used in the system, thesystem having wide flexibility of use. I

Lower stanchion 36 is installed projecting vertically from the platformof dolly 21 and is supported by adjusta'ble guy wires 37. An upperstanchion 38 is rotatable inside lower section 36 and carries a pad 39from which extends hollow first boom 41 connected by means of horizontalswivel pin 42 to pad 39 by means of a clevis 43. The outer end of firstboom 41 carries a second clevis 44 pinned by means of pin 46 totransverse yoke 47 in which is rotatable rod 48. One end of rod 48 ispinned by means of pin 49 to pad 51 on the inner end of hollow secondboom 52 which has a curved outer end 53. Ad-

relative to yoke 47 the outer end 53 of the second boom 52 may bebrought into alignment with a pan, mold, cavity or the like into whichthe product is to be dispensed. The various hoses for ingredients andcertain air supply hoses are carried up from dolly 21 and particularlyfrom console 22 through first boom '41 and thence through second boom 52to dispensing head 58 depending from end 53. The dispensing head 58hereinafter described in detail is attached to the ends of said hoses.

COMPONENT PUMPS A preferred pumping system uses three pumps, namely amain pump 26 to pump component A used in greatest quantity, a firstslave pump 28 to pump component B used in lesser quantity, and a secondslave pump to pump Freon or other gaseous foaming agent. The two slavepumps 25, 28, as hereinafter explained in detail, are preferably drivenby means of the valve system for air motor I 27 of master pump 26 andthe two slave pumps are preferably individually variable in stroke.

Master pump 26 is shown in FIG. 3. The pump itself is a double-actingpiston type having a cylinder 61 in which reciprocates piston 62 mountedon rod 63. The lower end of cylinder 61 is closed by disc 64 throughwhich piston 62 projects. Below disc 64 is pipe 65 extending to thebottom of drum 23. Check valve 66 is located at the bottom of pipe 65.Above valve 66 is a second piston 67 connected to the lower end of rod63 to reciprocate inside pipe 65. Piston '67 has a second check valve68. The discharge from pipe 65 is through port 69 in the upper end ofpipe 65. Fluid is drawn into pipe 65 on the upstroke of pistons '62 and67 and is also discharged through port 69, valve 68 being closed. On thedownstroke of pistons 62 and 67, piston 62 displaces part of the volumebelow disc 64, and valve 68 is opened and valve 66 closed. Hence, fluidis discharged through port 69 on both the upstroke and downstroke of thepump.

The pump motor 27 is mounted above pump 26 and consists of adouble-acting piston 76 reciprocable in cylinder 7-7, piston 76 being onthe same shaft 63 as pump piston 62. Motor cylinder '77 is formed withports 78, 78a, at opposite ends, ports 78, 78a, being connected by meansof conduits 79 and 79a respectively to console 22. As air is admitted toopposite ports 79, 79a, pistons 76 and 62 are caused to reciprocate intheir respective cylinders.

The valve system for air motor 27 is shown in simplified schematic form.The actual valve structure is of wellknown toggle type which iscommercially available, A D- type slide 81 is fixed by fittings 82, 82a,for reciprocation with rod 63 inside valve body '83. Valve body 83 isformed with three adjacent ports 84, 85, 86, the length of slide 81being such as to establish communication between the center port 84 andeither of the two end ports 85, 86. A fourth port 87 for exhaust isformed in valve body 83 and establishes communication and thatparticular end ports 85, 86, which is not at a particular time incommunication with center port 84. Compressed air from console 22 isintroduced at center port 84. The function of the motor valve is toreverse direction of air motor 27 as piston 62 reaches each end of itsstroke. A feature of the invention is the fact that ports 85 and 86 ofthe valve body do not directly communicate with ports 78, 78a, of theair motor 27, but rather are connected by means of conduits 79, 79a, toconsole 22. The arrangement of the console 22, described in discussingthe piping diagram FIG. 2 at a later section of this specificationinsures that valve 81 controls reciprocation of the air motors for mainpump 26 and also for the two slave pumps 25, 28.

The two slave pumps 25, 28, are essentially the same in structure exceptfor capacity and hence only one such pump 25 is illustrated in FIG. 4.Pump cylinder 91 comprises a tube, the opposite ends of which fit intoend blocks 93, 93a, which are tied together by jacket 94. Pump rod 96which extends through end blocks 93, 930, carries piston 97 which inthis case comprises plastic discs 98 held in place by a plurality ofmetal discs 99 fixed to rod 96. Inlet and outlet ports 101, 102, areformed in lower end disc 93 and inlet and outlet ports 101a, 102a, areformed in middle end block 93a. Check valves 103 are installed at eachport 101, 102, so that the direction of flow is as shown by the arrowsin FIG. 4.

Above middle end block 93a is motor cylinder 104 which carries at itsupper end an upper end disc 93b. Lower air port 106 and upper air port106a are formed in middle and upper end blocks 93a, 93b, respectively. Afirst piston 107 is fixed to rod 96. The upper end 108 of rod 96 isexternally threaded and receives internally threaded sleeve 109 whichcarried upper piston section 111 at its lower, end. Sleeve 109 extendsexternally of upper plug 93!). By turning rod 108 and sleeve 109 equalangular distances in opposite directions, the two pistons 107, 111, maybe moved toward or away from each other. Since each piston has its ownring 112 which seals against cylinder 104, the space 113 between thepistons is for practical purposes dead. Accordingly the stroke of rod 96may be adjusted by moving motor pistons 107, 111, toward and away fromeach other and this, in practical effect, adjusts the stroke of pumppiston 97. The outer end of each piston 107, 111, is formed with arounded nose 87 and discs 93a, 9312, with complementary recesses 88 inwhich seat O-rings 89. When piston 111, for example, approaches the endof the stroke, nose 87 seats on ring 89, forming an air cushion inrecess 88 which cushions the shock of the piston hitting the end of thecylinder.

MIXING HEAD Mixing head 58 is shown in FIG. 5. There is provided anupper block 121 and a lower block 122 each formed with an annular groove123 receiving an O-ring 124. The opposite ends of cylinder barrel 126fit into grooves 123 with O-rings 124 interposed between the edges ofthe barrel 126 and the bottoms of the grooves. A pair of diametricallyopposed studs 114 project from the periphery of upper block 121.Extending across the bottom of lower block 122 is a rod 115. A pair ofeye bolts 116 fit around studs, 114, the eyes, 117 thereof, beingopen-ie, not weldedso that excessive stress on bolts 116 causes the eyesto expand. The lower ends of bolts 116 extend through holes in rod andare retained in place by means of nuts 118. When it is desired todisassemble head 58, nuts 118 are removed, thereby separating blocks121, 122, and enabling the cylinder barrel 126 to be removed. If, as hasbeen mentioned, the pressure inside cylinder 126 becomes excessive, theeyes 117 open until the blocks 121, 122, move apart a sufiicientdistance so that the contents of the head may escape around the edges ofbarrel 126. The butt joints provided by grooves 123 enable the fluidinside head 58 to escape without interference from O-rings 124, aparticular feature and advantage of the invention which prevents head 58from exploding under excessive pressure.

Extending through head 58 is mixer shaft 127. The

lower end 128 of shaft 127 is necked and is received in a bore in lowerblock 122, it being noted that the discharge nipple 129 of block 122 isoff-center, thereby enabling block 122 to serve as a lower bearing forshaft 127. The upper end of shaft 127 extends through block 121 and isconnected by means of coupling 131 to the shaft 132 of conventional airturbine 133 carried on the upper end of block 121. The arrangementheretofore described does not require external lubrication, in that thefluids dispensed through the mixing head provide their own lubricationfor the metal-to-metal bearings. Turbine 133 is driven by compressed airand has a manual valve 135 controlling turbine 133.

Upper head 121 has three inlet ports for the three components beingmixed. The port 136 for the thinner viscosity component is directedradially inwardly toward shaft 127, the bore 137 of head 121 beinggreater than the diameter of shaft 127 to provide an annular space downwhich the component flows from port 136. Similarly the liquified Freonport 138 is radially disposed at about the level of component B port136. Shaft 127 is roughened or knurled in the extension 135 which fitsinto bore 137 so that the Freon and thinner component are at leastpartially mixed together as soon as they are received in the mixing head58. An annular chevron packing seal 139 is recessed into the upper endof head 121 and seals against shaft 127. Radial openings 141 areprovided above seal 139 so that if component leaks out through seal 139it escapes through openings 141.

The thicker viscosity component is introduced into mixing head 121through port 142 which enters the mixing chamber in an axial directionspaced radially outwardly from the center of shaft 127.

Above ports 136, 142, are plug valves 143, of conventional type, thestems 144 of the valves being diametrically opposed. A single actuatinghandle 146 is provided controlling both valves 143 so that the twocomponents are turned on and off simultaneously. One of the valve stems146 carries a cam 147. Pilot air valve body 148 is positioned inproximity to cam 147 and has a cam follower 149 on its stem 151. Whenthe handle 146 is turned to open the valve the compressed air valve 148is switched from one outlet to another. Valve inlet 152 is connected byhose 150 to the source of compressed air for driving mixing head turbine133. Valve 148 is connected by hoses to console 22 and is used as pilotair to control the actuation of valves for all pump air motors for theingredients. This prevents back-pressure from building up in the hosesleading to the component valves 143 at the dispensing head. Passageway138 connects with valve body 143a having branch 153 connected to asource of Freon at console 22. Valve handle 154 on body 152 is used toconnect passage 138 with solvent flush pot 33 when it is necessary toclean the equipment.

The mixing head body 126 contains agitator propellers 156, 157, ateither end of cylinder 126 mounted on shaft 127, the blades ofpropellers 156, 157, being pitched so as to create upward motion of thefluid in a direction counter to downward flow through head 58. Counterflow insures thorough mixing of the ingredients. Further, an annularshroud 158 is formed around the periphery of upper propeller 156. Thecross section of the shroud 158 as shown in FIG. 6 is such that liquidis directed upward and radially inward by the shroud, thereby causingrecirculation of the heavier component to augment mixing of thecomponents together. It will be understood that the Freon is heavierthan the other components and hence by reason of centrifugal force tendsto move toward the cylinder wall 126 and might, were it not for meansherein provided, run down the cylinder wall without proper mixing withthe other components. Shroud 158 tends to direct the Freon back towardthe shaft 127 for recirculation.

Shaft 127 carries a number of radially extending pins 159 and radiallyinward extending pins 161 are formed on the interior wall of cylinder126, the various pins 159, 161, resembling a turnstile. The pins insurethorough mixing of the components as they move from the top to thebottom of cylinder 126 and are discharged through discharge orifice 129.

BACK PRESSURE VALVE Immediately below mixing head 58 is back pressurevalve 171. It will be understood that a foaming agent such as Freon 12must be maintained above its vapor pressure up to the time of beingdispensed or the discharge will not be a froth foam. To insure thisresult, back pressure valve 171 is preferably installed below the mixinghead 58 in such fashion that no fluid is discharged from the mixing headat a pressure below a preselected pressure, which for practical purposesshould be about 80 p.s.i. for Freon 12. Valve 171 is contained in outertubular casing 172 threaded at either end, the upper end 173 beingthreaded to the discharge nipple 129 of mixing head 58. A tubularperforated support 173 is positioned inside casing 172 with an annularspace 174 between the two cylindrical members. A compressed air inlet176 is installed in valve casing 172 and communicates with annular space174. Immediately inside tubular support 173 is a resilient tubulardiaphragm 177 which is normally straight and open at either end. Theends 178 of diaphragm 177 are folded over to the outside of tubularsupport 177 and are jammed between the opposite ends of casing 172 andthe end edges of support 173. Diaphragm 177 is preferably fabricated ofrubber hose reinforced with a breaker strip of cloth, which cloth is cuton the bias. When compressed air is supplied to inlet 176 through hose179 diaphragm 177 tends to contract from the solid line position shownin FIG. 5 to the dotted line position thereby closing the passagewaythrough valve 171. However, the pres- .sure of the fluid attempting toflow through the valve when it overcomes the pressure of the compressedair restores diaphragm 177 to solid line position and permits theemission of fluid discharged from mixing head 58, which pressure is inall instances not less than the pressure of the incoming compressed air.Air is controlled by valve 180 to a source of compressed air orexhausted to atmosphere.

EXPANSION CHAMBER Below back pressure valve 171 is expansion chamber 181which comprises a coupling 182 screwed onto the lower end 183 of valvebody 171 which flares out to an increased diameter 184 and thencecontracts to a diameter 186 approximately equal to that at the entrance.End '183 is threaded to receive coupling 182 or an adapter for a hose todirect the fluid to a point of discharge. An .apertured plate 187 isinterposed transversely across expansion chamber 181 housing at itspoint 184 of maximum diameter, the apertures 188 in plate 187 beinglocated adjacent the periphery thereof. The cavity 189 above plate 187tends to collect the foam forming upon discharge from back pressurevalve 171 and emits the foam in a relatively straight line flow throughaperture 186, thereby eliminating swirling or snarling of the dischargestream which might otherwise result.

PIPING SYSTEM A convenient piping system installed in console 22 isshown in FIG. 2. A source of compressed air such as a portable aircompressor or compressed air tank is connected to inlet 201 at console22 and is directed by means of conduit 202 to a water trap 203 andthence by means of conduit 204 to first compressed air manifold 206, thepressure of which is indicated by gauge 206A. A portion of thecompressed air may be diverted through oiler 207 and thence by means ofconduit 208 to outlet 209 on console 22, thus providing a convenientsource of oiled air for auxiliary equipment. Part of the oiled air inconduit 208 .is .diverted by conduit 211 to secondary outlet 212.Another part of the oiled air passes through conduit 213 to port B ofvalve 214 and by conduit 216 from port 214F to oiled air manifold 217,valve 214 being controlled as hereinafter described. A portion of theair in manifold 206 is conducted by conduit 218 to secondary manifold219. Auxiliary air fans for spray equipment may be connected intomanifold 217, thus line 221 for fan air outlet 222 may be controlled bymeans of valve 223 which is a manually adjustable pressure regulatingvalve. Similarly conduit 224 leads from manifold 219 to outlet 226 andvalve 227 controls air pressure at outlet 226. Air for air masks leadsfrom manifold 206 through conduit 228, to outlet 229 and conduit 231leads to a second mask air outlet 232. Air for flush pot 33 istransmitted from manifold 206 by conduit 233 to outlet 234. Air turbine133 on mixing head 58 is supplied by means of conduit 236 from manifold206 through air regulator 237 and conduit 238 and thence to outlet 239whence it is conducted by means of a suitable hose through booms 41 and52 to air turbine 133 and its manual valve 135. This air also suppliespilot valve 148 and inlet 176 of back pressure valve 171.

The pumping system is largely controlled from the console pneumaticsystem. Pilot air from air valve 148 on mixing head 58 enters console 22through inlet 240 01 inlet 241, depending on the setting of valve 148,and is transmitted by conduits 242 and 242a to the D and G ports ofvalve 214, respectively. The setting of valve 148 controls the movementof the valve spool in valve 214. The B port of valve 214 is connected byconduit 213 to the source of oiled compressed air, as has beenexplained. The A port is connected by conduit 244 to exhaust airterminal 246. The F, or discharge port, of valve 214 is connected bymeans of conduit 216 to oiled air manifold 217. Thus valve 148 controlsoiled air pressure or exhaust in manifold 217.

Oiled compressed air is directed from manifold 217 by conduit 251 tooutlet 252 which is connected by a hose (not shown) to middle valve port84 of valve body 83 for air motor 27 of the main or master pump 26. Thereturn lines from the two end valve ports 85, 86, of valve 83, terminateat terminals 253, 254, respectively, of console 22 and are connectedthence by means of conduits 255, 256, to the D and G ports respectively,of valve 257 and also to the D and G ports of valves 258 and 259. The Dand G ports of the respective valves control movements of the spoolswithin said valves. The A and C ports of valves 257, 258, and 259 areconnected by conduits 261, 262, to exhaust terminal 246. The air supplyfor the center port B of valve 257 is connected by conduit 263 to oiledair manifold 217 with pressure regulating valve 264 interposed. The Eand F ports of valve 257 lead respectively by means of conduits 266 and267 to console outlets 268 and 269, respectively, which are connected bymeans of '79, 79a hoses to the master pump air motor ports 78, 78a.Hence, the air supply from the master pump air motor valve ports 85 and86 which enters console 22 through connections 253 and 254 controls theair supply to motor 27.

The B port, or air inlet port of valve 259, is connected by means ofconduit 271 to oiled air manifold 217 with pressure regulating valve 272interposed. Thus valve 272 controls the pressure into valve 259. The Eand F ports of valve 259 are connected by conduits 273, 274, to slavepump terminals 276, 277, which are connected by hoses to the air motorports 106, 106a, for slave pump 28.

The air inlet or B port of valve 258 is connected by conduit 281 tovalve 283 and thence to oiled air manifold 217. By adjustment of valvev283 the pressure of air to Freon pump 25 is controlled. Freon pump 25may be installed on console 22. The Freon supply is connected throughconnection 286 on the console and thence by means of conduit 287 toports 101 and 101a of Freon pump 25. Guage 288 mounted on console 22 isconnected 10 into conduit 287 and shows the Freon pressure. The Freondischarge from .pump ports 102 and 102a is connected by conduit 289 toFreon discharge terminal 291 and is then connected by a suitable hose tomixing head port 138.

Valve 258 controls Freon pump 25. Its E and F ports are connected byconduits 292 and 293 to ports 106 and 106m respectively of the air motorfor Freon pump 25.

Although I have described the present invention in some detail forpurposes of illustration and example, it is understood that variouschanges and modifications may be practiced within the spirit of theinvention and scope of the appended claims.

What is claimed is:

1. A foam depositor system comprising a first container for a firstcomponent, a first positive displacement pump for pumping firstcomponent from said first container, a first master fluid motor fordriving said first pump, first valve means responsive to actuation ofsaid first pump, a second container for a second component, secondpositive displacement pump for pumping second component from said secondcontainer, a second slave fluid motor for driving said second pump, athird container for a third component, a third positive displacementpump for pumping third component from said third container, a thirdslave fluid motor for driving said third pump, a source of fluid underpressure, means for directing fluid under pressure to said first masterfluid motor, control means responsive to said first valve means fordriving said fluid motors substantially synchronously from said sourceof fluid under pressure, means for independently regulating the fluidunder pressure to each of said second and third slave fluid motors formaintaining the speed of said motors the same thereby compensating forvariation in the relative viscosities of said components, a dispendinghead, conduit means for transmitting components from each of said pumpsto said dispensing head and maintaining said components separating priorto reaching said dispensing head, a back pressure valve controllingdischarge from said dispensing head, adjustment means for said backpressure valve whereby components are discharged from said dispensinghead only when the pressure of said component exceeds a predeterminedpressure at said back pressure valve, mixing means in said dispensinghead thoroughly mixing said components together under pressure, andmeans for varying the stroke of each of said second and third slavefluid motors thereby to vary the respective proportion of said secondand third components transmitted to said dispensing head relative tofirst component transmitted from said first pump.

2. A foam depositor system comprising a first container for a firstcomponent, a first pump for pumping first component from said firstconductor, a first fluid motor for driving said first pump, first valvemeans responsive to actuation of said first pump, a second container fora second component, a second pump for pumping second component from saidsecond container, a second fluid motor for driving said second pump, athird container for a third component, a third pump for pumping thirdcomponent from said third container, a third fluid motor for drivingsaid third pump, a source of fluid under pressure, control meansresponsive to said first valve means for driving each of said fluidmotors substantially synchronously from said source of fluid underpressure, a dispensing head, conduit means for transmitting componentsfrom each of said pumps to said dispensing head and maintaining saidcomponents separated prior to reaching said dispensing head, mixingmeans in said dispensing head for mixing said components together, andsecond valve means interposed between said control means and at leastone of said air motors for adjusting the speed of said last-named airmotor without affecting the volume of discharge of said last-named airmotor and without affecting the speed of the other said air motor.

(References on following page) 1 1 12 References Cited by the Examiner3,011,444 12/1961 H%bson 103-6 3,013,497 12/1961 SC neider 103--6 UNITEDSTATES PATENTS 3,035,775 5/1962 Edwards et a1. 239-142 1,590,578 6/1926Harris et a1. 222145 3 3 741 5 19 3 Hilts 222 1 2,073,779 3/1937 Bramsen239-304X 5 3,049,267 8/1962 Edwards et a1. 222-134 2,633,154 3/ 1953Eastman 3,071,293 1/1963 Lewis-Smith 61131. 222-334X 2,746,641 5/ 1956King 222132 X 3,134,508 5/1964 Bayer 61 a1. 222 135 2,762,652 9/1956Carter 239-303 X 3,146,950 9/1964 Lancaster 239-428 X 2,862,765 12/1958Wing 239-303 X 2,895,644 7/1959 Panda 222134 10 RAPHAEL M. LUPO, PrimaryExaminer. 8 7/ 19 Kraft 222 X LOUIS l DEMBQ Examiner 2,982,511 5/1961Connor 2515

2. A FOAM DEPOSITOR SYSTEM COMPRISING A FIRST CONTAINER FOR A FIRSTCOMPONENT, A FIRST PUMP FOR PUMPING FIRST COMPONENT FROM SAID FIRSTCONDUCTOR, A FIRST FLUID MOTOR FOR DRIVING SAID FIRST PUMP, FIRST VALVEMEANS RESPONSIVE TO ACTUATION OF SAID FIRST PUMP, A SECOND CONTAINER FORA SECOND COMPONENT, A SECOND PUMP FOR PUMPING SECOND COMPONENT FROM SAIDSECOND CONTAINER, A SECOND FLUID MOTOR FOR DRIVING SAID SECOND PUMP, ATHIRD CONTAINER FOR A THRID COMPONENT, A THIRD PUMP FOR PUMPING THIRDCOMPONENT FROM SAID THIRD CONTAINER, A THIRD FLUID MOTOR FOR DRIVINGSAID THIRD PUMP, A SOURCE OF FLUID UNDER PRESSURE, CONTROL MEANSRESPONSIVE TO SAID FIRST VALVE MEANS FOR DRIVING EACH OF SAID FLUIDMOTORS SUBSTANTIALLY SYNCHRONOUSLY FROM SAID SOURCE OF FLUID UNDERPRESSURE, A DISPENSING HEAD, CONDUIT MEANS FOR TRANSMITTING COMPONENTSFROM EACH OF SAID PUMPS TO SAID DISPENSING HEAD AND MAINTAINING SAIDCOMPONENTS SEPARATED PRIOR TO REACHING SAID DISPENSING HEAD, MIXINGMEANS IN SAID DISPENSING HEAD FOR MIXING SAID COMPONENTS TOGETHER, ANDSECOND VALVE MEANS INTERPOSED BETWEEN SAID CONTROL MEANS AND AT LEASTONE OF SAID AIR MOTOR WITHOUT AFFECTING THE VOLUME OF SAID LAST-NAMEDAIR MOTOR WITHOUT AFFECTING THE VOLUME OF DISCHARGE OF SAID LAST-NAMEDAIR MOTOR AND WITHOUT AFFECTING THE SPEED OF THE OTHER SAID AIR MOTOR.